Protected shareware

  • US 6,330,549 B1
  • Filed: 10/30/1997
  • Issued: 12/11/2001
  • Est. Priority Date: 10/30/1997
  • Status: Expired due to Term
First Claim
Patent Images

1. A method for protecting a computer program from unauthorized use independently of any methodology for distributing the computer program to prospective users, the computer program including an embedded protective code, the method comprising the steps of:

  • (a) inhibiting via the embedded protective code at least one functional feature of the computer program from running on a user computer until the user computer receives an authorization message that is digitally signed by an authorized party using a secret signing key, the secret signing key being associated with a public checking key;

    (b) providing the embedded protective code with access to the public checking key;

    (c) running an integrity self-check over the computer program to confirm that the computer program is in an anticipated state, the integrity self-check being embedded in the computer program;

    (d) communicating the authorization message to the user computer;

    (e) applying the public checking key to the authorization message for authenticating it; and

    (f) enabling said functional feature to run on the user computer if the authorization message is authenticated and if the integrity self-check result confirms that the computer program is in the anticipated state.

View all claims

    Thank you for your feedback